Imperial Socket Cap Screw

Socket Cap Screws

1960 Series

Unified National Coarse

S310 - UNC Bare Steel

ANSI/ASME B18.3

2003

Socket Cap Screw Technical Drawing
Diameter d #4-40 #6-32 #8-32 #10-24 1/4-20 5/16-18 3/8-16 7/16-14
Diameter Code 004 006 008 010 014 016 018 020
t min. .051 .064 .077 .090 .120 .151 .182 .213
s 3/32 7/64 9/64 5/32 3/16 1/4 5/16 3/8
.094 .109 .141 .156 .188 .250 .312 .375
k max. .112 .138 .164 .190 .250 .312 .375 .438
d1 max. .183 .226 .270 .312 .375 .469 .562 .656
R.S. Torque (in-lb) 14.1 26.2 48.0 69.5 166 342 608 973
Length Code Pkg.
1/4 0025 100 100 100 100 100
5/16 0031 100 100
3/8 0038 100 100 100 100 100 100
1/2 0050 100 100 100 100 100 100 100 100
5/8 0063 100 100 100 100 100 100 100
3/4 0075 100 100 100 100 100 100 100 100
7/8 0088 100 100 100 100 100
1 0100 100 100 100 100 100 100 100 100
1-1/4 0125 100 100 100 100 100 100 100
1-1/2 0150 100 100 100 100 100 100 100
1-3/4 0175 100 100 100 100 100 100
2 0200 100 100 100 100 100 100 50
2-1/4 0225 100 100 100 50 50
2-1/2 0250 100 100 100 100 50 50
2-3/4 0275 100 100 50 50
3 0300 100 100 100 50 50
3-1/4 0325 100 100 50 50
3-1/2 0350 100 100 100 50 50
3-3/4 0375 100 100 50 50
4 0400 100 100 100 50 50
4-1/4 0425 100 100 50
4-1/2 0450 100 100 100 50 25
4-3/4 0475 100 100 50
5 0500 100 100 50 25
5-1/2 0550 100 100 50
6 0600 100 100 25
6-1/2 0650 100 25
7 0700 100 25
7-1/2 0750 100 25
8 0800 100 25

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Diameter d 1/2-13 5/8-11 3/4-10 7/8-9 1-8 1 1/8-7 1 1/4-7 1 1/2-6
Diameter Code 024 026 028 030 034 036 038 044
t min. .245 .307 3.70 .432 .495 .557 .620 .745
s 3/8 1/2 5/8 3/4 3/4 7/8 7/8 1
.375 .500 .625 .750 .750 .875 .875 1.000
k max. .500 .625 .750 .875 1 1.125 1.250 1.500
d1 max. .750 .938 1.125 1.312 1.5 1.688 1.875 2.250
R.S. Torque (in-lb) 1484 2792 4952 7991 11979 16968 23944 41661
Length Code Pkg.
1/2 0050 50
5/8 0063 50
3/4 0075 50
7/8 0088 50
1 0100 50 50 25
1-1/4 0125 50 50 25
1-1/2 0150 50 50 25 10 10
1-3/4 0175 50 50 25 10
2 0200 50 50 25 10 10
2-1/4 0225 50 25 25 10 10
2-1/2 0250 50 25 25 10 10 1
2-3/4 0275 50 25 25 10 10
3 0300 50 25 25 10 10 1 1
3-1/4 0325 25 25 25 10 10
3-1/2 0350 25 25 25 10 10 1 1
3-3/4 0375 25 25 25 10 1
4 0400 25 25 25 10 10 1 1 1
4-1/4 0425 25 25 25 10
4-1/2 0450 25 25 25 10 10 1 1
4-3/4 0475 25 25 25 10
5 0500 25 25 25 10 10 1 1 1
5-1/2 0550 25 10 10 10 10 1 1
6 0600 25 10 10 10 10 1 1 1
6-1/2 0650 10 10 10 10 10 1 1
7 0700 10 10 10 10 10 1 1
7-1/2 0750 10 10 10 10
8 0800 10 10 10 10 10 1 1
8-1/2 0850 1 10 10 1
9 0900 1 10 10 10 1 1 1
9-1/2 0950 1 10 10 1
10 1000 1 10 10 10 1 1 1
11 1100 1 10 10 1 1
12 1200 1 10 10 1 1 1
13 1300 1
14 1400 1 1
16 1600 1
Order Number -> 1/4 x 2-1/2 = S310-014-0250 (Diameter Code x Length Code)

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Socket Cap Screws

1960 Series

Unified National Fine

S313 - UNF Bare Steel

ANSI/ASME B18.3

1986

Socket Cap Screw Technical Drawing
Diameter #10-32 1/4-28 5/16-24 3/8-24 7/16-20 1/2-20 5/8-18 3/4-16 1-14 1 1/4-12 1 1/2-12
Diameter Code 010 014 016 018 020 024 026 028 034 038 044
t min. .090 .120 .151 .182 .213 .245 .307 3.70 .495 .620 .745
s 5/32 3/16 1/4 5/16 3/8 3/8 1/2 5/8 3/4 7/8 1
.156 .188 .250 .312 .375 .375 .500 .625 .750 .875 1.000
k max. .190 .250 .312 .375 .438 .500 .625 .750 1 1.250 1.500
d1 max. .312 .375 .469 .562 .656 .750 .938 1.125 1.5 1.875 2.250
R.S. Torque (in-lb) 69.5 166 342 608 973 1484 2792 4952 11979 23944 41661
Length Code Pkg.
3/8 0038 100
1/2 0050 100 100 100 100
5/8 0063 100 100 100
3/4 0075 100 100 100 100
7/8 0088 100 100 100
1 0100 100 100 100 100 100 50 50
1-1/4 0125 100 100 100 100 100 50 50
1-1/2 0150 100 100 100 100 100 50 50
1-3/4 0175 100 100 100 100 50 50 25
2 0200 100 100 100 100 50 50 50 25
2-1/4 0225 100 50 50 25
2-1/2 0250 100 100 100 50 50 25 25 10 1
2-3/4 0275 50 25
3 0300 100 100 50 50 50 25 25 10 1
3-1/2 0350 100 100 50 25 25 25 10 1
4 0400 100 100 50 25 25 25 10 1 1
4-1/2 0450 25 25 10 1
5 0500 25 25 10 1 1
6 0600 25 10
Order Number -> 1/4 x 2-1/2 = S313-014-0250 (Diameter Code x Length Code)

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Diameter d d d <= 1/2 d > 1/2
Hardness (HRC) 39-45 37-45
Tensile Strength (psi) 180,000 min. 170,000 min.
Yield Strength at 0.2% Offset (psi) 153,000 min. 153,000 min.
Elongation (%) 10 min. 10 min.

R.S. Torque = Recommended Seating Torque

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